Aplikasi marka rm223 pada introduksi aroma pandan Wangi ke varietas nonaromatik ciherang

Abstract

Marka-marka aromatik kodominan berbasis badh2 (badh2-based) yang tersedia pada saat ini tidak dapat membedakan padi aromatik Indonesia kelompok 2 dari varietas nonaromatik. Pandan Wangi termasuk dalam kelompok tersebut. Pandan Wangi hanya dapat dibedakan dari varietas nonaromatik menggunakan marka aromatik kodominan terkait gen badh2 (badh2-related), RM223. Penelitian ini merupakan studi awal fragrantgenotyping padi aromatik Indonesia dan aplikasi marka RM223 dalam rekayasa varietas aromatik baru berbasis Pandan Wangi. Introduksi dilakukan secara persilangan terarah (site-directed crossing) untuk menghindari produk transgenik yang pemasarannya terhambat oleh regulasi GMO (Genetically Modified Organisms) yang ketat. Pandan Wangi disilang dengan Ciherang, kemudian dibackcross dengan Ciherang sampai BC2F1. Pada setiap generasi persilangan/backcross dilakukan seleksi PCR berbantuan marka RM223. Hinga BC2F1 Ciherang-Pandan Wangi telah berhasil dikonstruksi. Selain itu didapatkan kemungkinan adanya 2 kelompok tipe mutasi ekson 7 gen badh2 pada varietas aromatik Indonesia. RM223 dapat mendeteksi native badh2 pada Ciherang, badh2 termutasi pada Pandan Wangi serta heterozygot badh2 pada progeni persilangan (F1, BC1, dan BC2).

Various codominant badh2-based fragrant markers are unable to discriminate group 2 Indonesia fragrant from non-fragrant rice. Pandan Wangi is one of group 2 member. Only badh2-related codominat fragrant marker RM223 has been able to distinguish Pandan Wangi form those of non-fragrant samples. In this research, preliminary fragrantgenotyping studies of Indonesia fragrant rice was carried out, as well as the use of RM223 as marker for new fragrant variety engineering based on Pandan Wangi. To avoid strict GMO (Genetically Modified Organisms) regulations, aroma introduction was carried out through site-directed crossing, to generate non-transgenic plant product, Pandan Wangi was crossed with Ciherang, and further backcrossed to Ciherang until BC2F1. RM223 marker-assisted PCR was used to select progeni in every cross and backcross generation. Up to BC2F1 Ciherang-Pandan Wangi has been successfully constructed. In addition, there may be at least 2 different group of exon 7 badh2 gene mutation among Indonesia fragrant rice varieties. RM223 was able to identify native, mutated, and heterozygous badh2 gene within Ciherang, Pandan Wangi, and progenies (F1, BC1F1, and BC2F1); respectively.